Anatomical patterns of infantile hemangioma (IH) of the extremities (IHE).

BACKGROUND: From 18% to 30% of infantile hemangiomas (IH) are located on the extremities (IHE). They can be divided into localized, segmental, and minimal or arrested growth (IH-MAG) subtypes.

OBJECTIVE: We sought to correlate localization of IHE with the anatomy of the arterial vascular supply.

METHODS: All children with segmental IHE and IH-MAG presenting to our department of pediatric dermatology from 2002 to 2015 were evaluated. Hemangiomas were mapped and their patterns were analyzed.

RESULTS: Most IHE were unilateral (105/109). Two thirds (68/109) were located on the upper, and one third (41/109) on the lower extremities. Distal locations were more frequently affected. Segmental IHE were more common (upper extremities 83.8%; lower extremities 56.1%) than IH-MAG (16.2% and 43.9%, respectively). Ulceration occurred in 5.5%. Localization of IHE was found to correspond to supply areas of embryonic arterial variants.

LIMITATIONS: This was a retrospective study. Only segmental IHE and IH-MAG were evaluated. Angiographic studies were not performed.

CONCLUSION: The location of IHE may be related to variant anatomy of arterial supply during embryo fetal development. We hypothesize that this contributes to temporary regional tissue hypoxia during early fetal development, which is a known stimulus for the proliferation of hemangioma stem cells.